Relevant bibliographies by topics / NS5b

Academic literature on the topic 'NS5b'

Author: Grafiati
Published: 4 June 2021
Last updated: 6 February 2022

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Journal articles on the topic "NS5b"

1

Wong, Mun-Teng, and Steve S. Chen. "Human Choline Kinase-α Promotes Hepatitis C Virus RNA Replication through Modulation of Membranous Viral Replication Complex Formation." Journal of Virology 90, no. 20 (August 3, 2016): 9075–95. http://dx.doi.org/10.1128/jvi.00960-16.

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ABSTRACTHepatitis C virus (HCV) infection reorganizes cellular membranes to create an active viral replication site named the membranous web (MW). The role that human choline kinase-α (hCKα) plays in HCV replication remains elusive. Here, we first showed that hCKα activity, not the CDP-choline pathway, promoted viral RNA replication. Confocal microscopy and subcellular fractionation of HCV-infected cells revealed that a small fraction of hCKα colocalized with the viral replication complex (RC) on the endoplasmic reticulum (ER) and that HCV infection increased hCKα localization to the ER. In the pTM-NS3-NS5B model, NS3-NS5B expression increased the localization of the wild-type, not the inactive D288A mutant, hCKα on the ER, and hCKα activity was required for effective trafficking of hCKα and NS5A to the ER. Coimmunoprecipitation showed that hCKα was recruited onto the viral RC presumably through its binding to NS5A domain 1 (D1). hCKα silencing or treatment with CK37, an hCKα activity inhibitor, abolished HCV-induced MW formation. In addition, hCKα depletion hindered NS5A localization on the ER, interfered with NS5A and NS5B colocalization, and mitigated NS5A-NS5B interactions but had no apparent effect on NS5A-NS4B and NS4B-NS5B interactions. Nevertheless, hCKα activity was not essential for the binding of NS5A to hCKα or NS5B. These findings demonstrate that hCKα forms a complex with NS5A and that hCKα activity enhances the targeting of the complex to the ER, where hCKα protein, not activity, mediates NS5A binding to NS5B, thereby promoting functional membranous viral RC assembly and viral RNA replication.IMPORTANCEHCV infection reorganizes the cellular membrane to create an active viral replication site named the membranous web (MW). Here, we report that human choline kinase-α (hCKα) acts as an essential host factor for HCV RNA replication. A fraction of hCKα colocalizes with the viral replication complex (RC) on the endoplasmic reticulum (ER) in HCV-infected cells. NS3-NS5B expression increases ER localization of wild-type, but not D288A mutant, hCKα, and hCKα activity facilitates the transport of itself and NS5A to the ER. Silencing or inactivation of hCKα abrogates MW formation. Moreover, hCKα is recruited by NS5A independent of hCKα activity, presumably through binding to NS5A D1. hCKα activity then mediates the ER targeting of the hCKα-NS5A complex. On the ER membrane, hCKα protein,per se, induces NS5A binding to NS5B, thereby promoting membranous RC formation and viral RNA replication. Our study may benefit the development of hCKα-targeted anti-HCV therapeutics.
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Chatterji, Udayan, Michael Bobardt, Andrew Tai, Malcolm Wood, and Philippe A. Gallay. "Cyclophilin and NS5A Inhibitors, but Not Other Anti-Hepatitis C Virus (HCV) Agents, Preclude HCV-Mediated Formation of Double-Membrane-Vesicle Viral Factories." Antimicrobial Agents and Chemotherapy 59, no. 5 (February 9, 2015): 2496–507. http://dx.doi.org/10.1128/aac.04958-14.

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ABSTRACTAlthough the mechanisms of action (MoA) of nonstructural protein 3 inhibitors (NS3i) and NS5B inhibitors (NS5Bi) are well understood, the MoA of cyclophilin inhibitors (CypI) and NS5A inhibitors (NS5Ai) are not fully defined. In this study, we examined whether CypI and NS5Ai interfere with hepatitis C virus (HCV) RNA synthesis of replication complexes (RCs) or with an earlier step of HCV RNA replication, the creation of double-membrane vesicles (DMVs) essential for HCV RNA replication. In contrast to NS5Bi, both CypI and NS5Ai do not block HCV RNA synthesis by way of RCs, suggesting that they exert their antiviral activity prior to the establishment of enzymatically active RCs. We found that viral replication is not a precondition for DMV formation, since the NS3-NS5B polyprotein or NS5A suffices to create DMVs. Importantly, only CypI and NS5Ai, but not NS5Bi, mir-122, or phosphatidylinositol-4 kinase IIIα (PI4KIIIα) inhibitors, prevent NS3-NS5B-mediated DMV formation. NS3-NS5B was unable to create DMVs in cyclophilin A (CypA) knockdown (KD) cells. We also found that the isomerase activity of CypA is absolutely required for DMV formation. This not only suggests that NS5A and CypA act in concert to build membranous viral factories but that CypI and NS5Ai mediate their early anti-HCV effects by preventing the formation of organelles, where HCV replication is normally initiated. This is the first investigation to examine the effect of a large panel of anti-HCV agents on DMV formation, and the results reveal that CypI and NS5Ai act at the same membranous web biogenesis step of HCV RNA replication, thus indicating a new therapeutic target of chronic hepatitis C.
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Sheng, Chun, Jing Wang, Jing Xiao, Jun Xiao, Yan Chen, Lin Jia, Yimiao Zhi, Guangyuan Li, and Ming Xiao. "Classical swine fever virus NS5B protein suppresses the inhibitory effect of NS5A on viral translation by binding to NS5A." Journal of General Virology 93, no. 5 (May 1, 2012): 939–50. http://dx.doi.org/10.1099/vir.0.039495-0.

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In order to investigate molecular mechanisms of internal ribosome entry site (IRES)-mediated translation in classical swine fever virus (CSFV), an important pathogen of pigs, the expression level of NS3 was evaluated in the context of genomic RNAs and reporter RNA fragments. All data showed that the NS5A protein has an inhibitory effect on IRES-mediated translation and that NS5B proteins suppress the inhibitory effect of NS5A on viral translation, but CSFV NS5B GDD mutants do not. Furthermore, glutathione S-transferase pull-down assay and immunoprecipitation analysis, associated with deletion and alanine-scanning mutations, were performed. Results showed that NS5B interacts with NS5A and that the region aa 390–414, located in the C-terminal half of NS5A, is important for binding of NS5B to NS5A. Furthermore, amino acids K399, T401, E406 and L413 in the region were found to be essential for NS5A–NS5B interaction, virus rescue and infection. The above-mentioned region and four amino acids were observed to overlap with the site responsible for inhibition of IRES-mediated translation by the NS5A protein. We also found that aa 63–72, aa 637–653 and the GDD motif of NS5B were necessary for the interaction between NS5A and NS5B. These findings suggest that the repression activity of the NS5B protein toward the role of NS5A in translation might be achieved by NS5A–NS5B interaction, for which aa 390–414 of NS5A and aa 63–72, aa 637–653 and the GDD motif of NS5B are indispensable. This is important for understanding the role of NS5A–NS5B interaction in the virus life cycle.
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Gao, Lu, Hideki Aizaki, Jian-Wen He, and Michael M. C. Lai. "Interactions between Viral Nonstructural Proteins and Host Protein hVAP-33 Mediate the Formation of Hepatitis C Virus RNA Replication Complex on Lipid Raft." Journal of Virology 78, no. 7 (April 1, 2004): 3480–88. http://dx.doi.org/10.1128/jvi.78.7.3480-3488.2004.

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ABSTRACT The lipid raft membrane has been shown to be the site of hepatitis C virus (HCV) RNA replication. The mechanism of formation of the replication complex is not clear. We show here that the formation of the HCV RNA replication complex on lipid raft (detergent-resistant membranes) requires interactions among the HCV nonstructural (NS) proteins and may be initiated by the precursor of NS4B, which has the intrinsic property of anchoring to lipid raft membrane. In hepatocyte cell lines containing an HCV RNA replicon, most of the other NS proteins, including NS5A, NS5B, and NS3, were also localized to the detergent-resistant membranes. However, when individually expressed, only NS4B was associated exclusively with lipid raft. In contrast, NS5B and NS3 were localized to detergent-sensitive membrane and cytosolic fractions, respectively. NS5A was localized to both detergent-sensitive and -resistant membrane fractions. Furthermore, we show that a cellular vesicle membrane transport protein named hVAP-33 (the human homologue of the 33-kDa vesicle-associated membrane protein-associated protein), which binds to both NS5A and NS5B, plays a critical role in the formation of HCV replication complex. The hVAP-33 protein is partially associated with the detergent-resistant membrane fraction. The expression of dominant-negative mutants and small interfering RNA of hVAP-33 in HCV replicon cells resulted in the relocation of NS5B from detergent-resistant to detergent-sensitive membranes. Correspondingly, the amounts of both HCV RNA and proteins in the cells were reduced, indicating that hVAP-33 is critical for the formation of HCV replication complex and RNA replication. These results indicate that protein-protein interactions among the various HCV NS proteins and hVAP-33 are important for the formation of HCV replication complex.
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Choi, Soo-Ho, Kyu-Jin Park, Byung-Yoon Ahn, Guhung Jung, Michael M. C. Lai, and Soon B. Hwang. "Hepatitis C Virus Nonstructural 5B Protein Regulates Tumor Necrosis Factor Alpha Signaling through Effects on Cellular IκB Kinase." Molecular and Cellular Biology 26, no. 8 (April 15, 2006): 3048–59. http://dx.doi.org/10.1128/mcb.26.8.3048-3059.2006.

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ABSTRACT Hepatitis C virus (HCV) NS5B protein is a membrane-associated phosphoprotein that possesses an RNA-dependent RNA polymerase activity. We recently reported that NS5A protein interacts with TRAF2 and modulates tumor necrosis factor alpha (TNF-α)-induced NF-κB and Jun N-terminal protein kinase (JNK). Since NS5A and NS5B are the essential components of the HCV replication complex, we examined whether NS5B could modulate TNF-α-induced NF-κB and JNK activation. In this study, we have demonstrated that TNF-α-induced NF-κB activation is inhibited by NS5B protein in HEK293 and hepatic cells. Furthermore, NS5B protein inhibited both TRAF2- and IKK-induced NF-κB activation. Using coimmunoprecipitation assays, we show that NS5B interacts with IKKα. Most importantly, NS5B protein in HCV subgenomic replicon cells interacted with endogenous IKKα, and then TNF-α-mediated IKKα kinase activation was significantly decreased by NS5B. Using in vitro kinase assay, we have further found that NS5B protein synergistically activated TNF-α-mediated JNK activity in HEK293 and hepatic cells. These data suggest that NS5B protein modulates TNF-α signaling pathways and may contribute to HCV pathogenesis.
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Grassmann, Claus W., Olaf Isken, Norbert Tautz, and Sven-Erik Behrens. "Genetic Analysis of the Pestivirus Nonstructural Coding Region: Defects in the NS5A Unit Can Be Complemented intrans." Journal of Virology 75, no. 17 (September 1, 2001): 7791–802. http://dx.doi.org/10.1128/jvi.75.17.7791-7802.2001.

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ABSTRACT The functional analysis of molecular determinants which control the replication of pestiviruses was considerably facilitated by the finding that subgenomic forms of the positive-strand RNA genome of BVDV (bovine viral diarrhea virus) are capable of autonomous replication in transfected host cells. The prototype replicon, BVDV DI9c, consists of the genomic 5′ and 3′ untranslated regions and a truncated open reading frame (ORF) encoding mainly the nonstructural proteins NS3, NS4A, NS4B, NS5A, and NS5B. To gain insight into which of these proteins are essential for viral replication and whether they act in cisor in trans, we introduced a large spectrum of in-frame mutations into the DI9c ORF. Tests of the mutant RNAs in terms of their replication capacity and their ability to support translation and cleavage of the nonstructural polyprotein, and whether defects could be rescued in trans, yielded the following results. (i) RNA replication was found to be dependent on the expression of each of the DI9c-encoded mature proteins NS3 to NS5B (and the known associated enzymatic activities). In the same context, a finely balanced molar ratio of the diverse proteolytic processing products was indicated to be crucial for the formation of an active catalytic replication complex. (ii) Synthesis of negative-strand intermediate and progeny positive-strand RNA was observed to be strictly coupled with all functional DI9c ORF derivatives. NS3 to NS5B were hence suggested to play a pivotal role even during early steps of the viral replication pathway. (iii) Mutations in the NS3 and NS4B units which generated nonfunctional or less functional RNAs were determined to becis dominant. Likewise, lethal alterations in the NS4A and NS5B regions were invariably noncomplementable. (iv) In surprising contrast, replication of functional and nonfunctional NS5A mutants could be clearly enhanced and restored, respectively. In summary, our data provide initial insights into the organization of the pestivirus replication machinery.
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Shimakami, Tetsuro, Makoto Hijikata, Hong Luo, Yuan Yuan Ma, Shuichi Kaneko, Kunitada Shimotohno, and Seishi Murakami. "Effect of Interaction between Hepatitis C Virus NS5A and NS5B on Hepatitis C Virus RNA Replication with the Hepatitis C Virus Replicon." Journal of Virology 78, no. 6 (March 15, 2004): 2738–48. http://dx.doi.org/10.1128/jvi.78.6.2738-2748.2004.

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ABSTRACT Hepatitis C virus (HCV) NS5A has been reported to be important for the establishment of replication by adaptive mutations or localization, although its role in viral replication remains unclear. It was previously reported that NS5A interacts with NS5B via two regions of NS5A in the isolate JK-1 and modulates the activity of NS5B RdRp (Y. Shirota et al., J. Biol. Chem., 277:11149-11155, 2002), but the biological significance of this interaction has not been determined. In this study, we addressed the effect of this interaction on HCV RNA replication with an HCV replicon system derived from the isolate M1LE (H. Kishine et al., Biochem. Biophys. Res. Commun., 293:993-999, 2002). We constructed three internal deletion mutants, M1LE/5Adel-1 and M1LE/5Adel-2, each encoding NS5A which cannot bind NS5B, and M1LE/5Adel-3, encoding NS5A that can bind NS5B. After transfection into Huh-7 cells, M1LE/5Adel-3 was replication competent, but both M1LE/5Adel-1 and M1LE/5Adel-2 were not. Next we prepared 20 alanine-substituted clustered mutants within both NS5B-binding regions and examined the effect of these mutants on HCV RNA replication. Only 5 of the 20 mutants were replication competent. Subsequently, we introduced a point mutation, S225P, a deletion of S229, or S232I into NS5A and prepared cured Huh-7 cells that were cured of RNA replication by alpha interferon. Finally, with these point mutations and cured cells, we established a highly improved replicon system. In this system, only the same five mutants were replication competent. These results strongly suggest that the interaction between NS5A and NS5B is critical for HCV RNA replication in the HCV replicon system.
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Svitkin, Yuri V., Arnim Pause, Marcelo Lopez-Lastra, Sandra Perreault, and Nahum Sonenberg. "Complete Translation of the Hepatitis C Virus Genome In Vitro: Membranes Play a Critical Role in the Maturation of All Virus Proteins except for NS3." Journal of Virology 79, no. 11 (June 1, 2005): 6868–81. http://dx.doi.org/10.1128/jvi.79.11.6868-6881.2005.

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ABSTRACT We developed an in vitro translation extract from Krebs-2 cells that translates the entire open reading frame of the hepatitis C virus (HCV) strain H77 and properly processes the viral protein precursors when supplemented with canine microsomal membranes (CMMs). Translation of the C-terminal portion of the viral polyprotein in this system is documented by the synthesis of NS5B. Evidence for posttranslational modification of the viral proteins, the N-terminal glycosylation of E1 and the E2 precursor (E2-p7), and phosphorylation of NS5A is presented. With the exception of NS3, efficient generation of all virus-specific proteins is CMM dependent. A time course of the appearance of HCV products indicates that the viral polyprotein is cleaved cotranslationally. A competitive inhibitor of the NS3 protease inhibited accumulation of NS3, NS4B, NS5A, and NS5B, but not that of NS2 or structural proteins. CMMs also stabilized HCV mRNA during translation. Finally, the formyl-[35S]methionyl moiety of the initiator tRNAMet was incorporated exclusively into the core protein portion of the polyprotein, demonstrating that translation initiation in this system occurs with high fidelity.
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Nutt, Jamie, James Grantham, Marilyn Smith, Emily Smith, Ashley Wedin, Aaron Tyler, Mauricio Miralles, Steve Kleiboeker, and Mark Wissel. "Performance of NS3, NS5a AND NS5b Hepatitis C Virus (HCV) Antiviral Resistance Sequencing Assays." Open Forum Infectious Diseases 4, suppl_1 (2017): S40. http://dx.doi.org/10.1093/ofid/ofx162.097.

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Abstract Background HCV genotype 1a (HCV g1a) followed by HCV g1b, –g2, and –g3 are the most common etiologic agents in the ~3 million current HCV-infections in the US. To achieve effective therapy, antiviral drug resistance testing is often essential but not fully available. Knowledge of both the genotype and the presence of HCV mutations in the genes of the major drug targets (NS3, NS5A and NS5B) can assist in optimal treatment selection. Methods The HCV genotype of 1000 HCV positive clinical plasmas and sera was determined (HCVg Direct, GenMark). Ten independent Sanger sequencing assays detecting antiviral drug resistance mutations in the genes encoding NS3, NS5a, and NS5b were developed. Six of these assays address mutations in all three genes in the two most common genotypes (HCV g1a and g1b). In addition, four more assays address mutations in NS5a and NS5b of HCV g2 and g3. These mutations are resistance determinants against 11 anti-HCV drugs as shown in Figure 1. A streamlined workflow employs conventional reverse transcriptase PCR, gel electrophoresis, spectrophotometry, bi-directional Sanger sequencing and reporting. The assays were designed to cover hot spot regions and capturing all known resistance mutations in NS3, NS5a and NS5b. Results Consistent with previous US HCV incidence reports, g1a, g1b, g2, and g3 comprised 99% of 1000 sequentially tested HCV patient specimens (62%, 12%, 11%, and 14%, respectively). Testing of more than 20 clinical samples each for g1a, g1b, g2, and g3 resulted in successful detection of NS3, NS5a, and NS5b mutations that confer drug resistance. The design successfully permitted detection of relevant mutations known to date for all 11 drugs. The number of reportable mutations range from 20 ‒ 36, 9 ‒ 49, and 10 ‒ 29 for the NS3, NS5a, and NS5b inhibitors, respectively (Figure 1). Conclusion These assays provide the most comprehensive commercially available antiviral drug resistance information to date for mutations in HCV NS3, NS5A, and NS5B. This testing will assist physicians in deciding on the most appropriate treatment options for their patients. Disclosures J. Nutt, Viracor Eurofins Laboratories: Employee, Salary; 
J. Grantham, Viracor Eurofins Laboratories: Employee, Salary; M. Smith, Viracor Eurofins Laboratories: Employee, Salary; E. Smith, Viracor Eurofins Laboratories: Employee, Salary; A. Wedin, Viracor Eurofins Laboratories: Employee, Salary; 
A. Tyler, Viracor Eurofins Laboratories: Employee, Salary; M. Miralles, Viracor Eurofins Laboratories: Employee, Salary; S. Kleiboeker, Viracor Eurofins Laboratories: Employee, Salary; M. Wissel, Viracor Eurofins Laboratories: Employee, Salary
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Aldunate, Fabián, Natalia Echeverría, Daniela Chiodi, Pablo López, Adriana Sánchez-Cicerón, Alvaro Fajardo, Martín Soñora, Juan Cristina, Nelia Hernández, and Pilar Moreno. "Pretreatment Hepatitis C Virus NS5A/NS5B Resistance-Associated Substitutions in Genotype 1 Uruguayan Infected Patients." Disease Markers 2018 (August 14, 2018): 1–9. http://dx.doi.org/10.1155/2018/2514901.

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Hepatitis C Virus (HCV) infection treatment has dramatically changed with the advent of direct-acting antiviral agents (DAAs). However, the efficacy of DAAs can be attenuated by the presence of resistance-associated substitutions (RASs) before and after treatment. Indeed, RASs detected in DAA treatment-naïve HCV-infected patients could be useful for clinical management and outcome prediction. Although the frequency of naturally occurring HCV NS5A and NS5B RASs has been addressed in many countries, there are only a few reports on their prevalence in the South American region. The aim of this study was to investigate the presence of RASs to NS5A and NS5B inhibitors in a DAA treatment naïve cohort of Uruguayan patients infected with chronic hepatitis C and compare them with reports from other South American countries. Here, we found that naturally occurring substitutions conferring resistance to NS5A and NS5B inhibitors were present in 8% and 19.2%, respectively, of treatment-naïve HCV genotype 1 infected patients. Importantly, the baseline substitutions in NS5A and NS5B herein identified differ from the studies previously reported in Brazil. Furthermore, Uruguayan strains subtype 1a clustered within all major world clades, showing that HCV variants currently circulating in this country are characterized by a remarkable genetic diversity.
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Dissertations / Theses on the topic "NS5b"

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Brandão, Ruben Alexandre Ribeiro. "Characterization of NS5A and NS5B resistance-associated substitutions from genotype 1 HCV infected patients in a Portuguese cohort." Master's thesis, Universidade Nova de Lisboa. Instituto Tecnologia Química e Biológica António Xavier, 2018. http://hdl.handle.net/10362/37051.

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Hepatitis C virus (HCV) is considered to be the leading cause of hepatocellular carcinoma (HCC). During the last years, several highly efficacy regimens of direct-acting antivirals (DAAs) with excellent rates of success became available. However, therapeutic failure may occur in up to 10% of treated individuals. Our aim was to study the profile of NS5 coding region RASs in DAA-naive genotype 1 HCV infected patients, as well as to ascertain an association between treatment failure and the presence of baseline NS5 RASs. A comparison between LiPA and Sanger sequencing genotyping methods was also assessed. Plasma RNA from 81 DAA-naïve GT1 HCV infected patients was extracted, followed by an in-house nested RT-PCR of the NS5 coding region. PCR products were purified, leading to Sanger population sequencing on the 3130xl ABI Genetic Analyzer. Sequences were aligned using ChromasPro v1.7.6, and analyzed online in hcv.geno2pheno.org. NS5A RASs were present in 28,4% (23/81) of all GT1 infected patients. The most commonly detected NS5A RAS was Y93C/H with a prevalence of 9,9% (8/81) in all GT1 infected patients. NS5B RASs showed a prevalence of 14,8% (12/81) in all GT1 infected patients, and were only detected in GT1b, being mainly represented by C316N accounting for 40% (10/25). The combined Q30H+Y93H NS5A RASs, were detected at baseline in one HIV/HCV GT1a co-infected patient who later failed a treatment with sofosbuvir/ledipasvir (SOF/LDV) for 12 weeks. An isolated Y93H mutation was also detected at baseline in a relapsing GT1b mono-infected patient. Overall 38,3% (31/81) of all GT1 HCV infected patients presented NS5 RASs at baseline, in which 58% (18/31) were co-infected with HIV/HCV. The obtained data supports the usefulness of resistance testing prior to treatment initiation, as a statistical significant association was found between treatment failure and the baseline presence of specific NS5 RASs, namely Y93C/H (p = 0.04).
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Fourar, Monia. "Dynamique structurale de l'ARN polymérase ARN dépendante NS5B : une nouvelle cible pour l'inhibition de la réplication du virus de l'hépatite C." Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20137.

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L'une des principales cibles pour la thérapie visant le virus de l'hépatite C (VHC) est l'ARN polymérase dépendante de l'ARN NS5B indispensable à la réplication du génome virale. NS5B est l'une des enzymes clefs du cycle virale de VHC et son activation met en jeu aussi bien des interactions intramoléculaires que des interactions avec des cofacteurs viraux et cellulaires au sein du complexe de réplication. Nous avons développé une nouvelle stratégie d'inhibition de NS5B basée sur l'élaboration de peptides courts dérivés de motifs exposés à la surface de l'enzyme dans le but de cibler les nombreuses interactions impliquées dans l'activation de cette protéine. En associant une analyse fine de la structure cristallographique de NS5B avec de la modélisation moléculaire, nous avons élaboré des peptides courts mimant les motifs « hotspot » de la protéine. Ces peptides ont été évalués sur système réplicon de génotype 1b et nous avons ainsi identifié un peptide leader Moon1 de 15 résidus correspondant à un motif hautement conservé du domaine "thumb". Dans ce travail, nous avons étudié en détail la structure et le mécanisme moléculaire de ce nouvel inhibiteur de NS5B. Moon1 inhibe l'activité polymérase de la forme sauvage de NS5B ainsi que celle de mutants résistants au inhibiteurs nucléosidiques et non nucléosidiques. Nous avons démontré que la fixation de Moon1 entraine un changement de conformation de NS5B et se fait préférentiellement avec NS5B dans une conformation fermée. Ce peptide inhibe spécifiquement l'interaction entre NS5B et l'ARN double brin, indépendamment de la présence d'ions métalliques et de manière dose-dépendante. Moon1 bloque la transition entre l'étape d'initiation de novo de la synthèse d'ARN et l'extension du primer. Nous avons démontré que les résidus essentiels à l'activité de Moon1 sont hautement conservés à travers les différents génotypes et sous-types de VHC. De plus, nous avons établi une séquence minimale pour l'activité de Moon1. Nos travaux permettent de valider l'intérêt d'une stratégie interfaciale ciblant une enzyme clef du cycle du VHC et les interactions intra et intermoléculaires nécessaires à son activation
The non-structural protein RNA-dependent RNA polymerase (RdRp) NS5B plays a key role in hepatitis C virus (HCV) replication and is currently considered as one of the most relevant target to develop safe anti-HCV agents. Although many small molecules have been identified as inhibitors of NS5B, very few are active in clinic. The structure and function of NS5B have been well characterized and as other polymerases, NS5B adopts a typical “right-hand” conformation containing the characteristic fingers, palm and thumb subdomains. The activation of NS5B requires conformational changes involving intramolecular contacts as well interactions with viral proteins and host factors in the replication complex. We developed a new strategy for NS5B inhibition based on short interfacial peptides derived from NS5B surface accessible motifs that target protein-protein interfaces or essential motifs involved in NS5B-activation. Combining the NS5B crystallogaphic structure and molecular modelling, we have designed short peptides derived from NS5B surface “hotspots” that were screened using HCV genotype 1b replicon cell system. We have identified Moon1, a short 15-residu peptide, derived from a well-conserved motif located in the NS5B thumb domain that inhibits HCV replication in the low nanomolar range. Moon1 tightly binds NS5B in a conformational-dependent manner and induces NS5B conformational changes. This peptide specifically inhibits double-stranded RNA/NS5B interactions in a dose-dependent and metal ions-independent manner. Moon1 blocks the transition between RNA de novo initiation and primer-extension. We showed that residues required for Moon-1 anti-polymerase activity are well-conserved among HCV genotypes and subtypes and a minimal Moon1 active motif was established. Taken together, these results demonstrate that NS5B structural dynamics constitute an attractive target for HCV chemotherapeutics and for the design of more specific new antiviral drugs
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Aissa, Larousse Jameleddine. "Etude de la variabilité génétique des régions NS3, NS5A et NS5B du virus de l'hépatite C chez des patients Tunisiens non traités." Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0434/document.

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Introduction : Le virus de l’hépatite C (VHC), est l’une des premières causes de pathologie hépatique dans le monde. Ce virus à ARN est responsable de l’hépatite C qui aboutit au développement de la cirrhose et du cancer du foie. Selon l’Organisation Mondiale de la Santé, le VHC infecte actuellement plus de 170 millions de personnes dans le monde, soit 3% de la population. L’hépatite C chronique connait toujours en Tunisie un taux de guérison faible pour le génotype 1 car le traitement standard actuellement disponible est la bithérapie interféron pégylé associé à la ribavirine. A l’heure actuelle, le développement de différentes molécules ciblant spécifiquement le VHC, appelées les antiviraux à action directe (AAD), apparait comme une potentielle révolution dans le traitement de l’infection par le VHC.Ces AAD comprennent les inhibiteurs de protéase (IP), les inhibiteurs nucléos(t)idiques (IN) et les inhibiteurs non-nucléosidiques (INN) de la polymérase NS5B ainsi que les inhibiteurs de la protéine NS5A. La quasi-espèce virale est formée d’un mélange complexe de variants viraux parmi lesquels se trouvent des variants associés à des degrés variables à la résistance aux AAD. Ces variants peuvent donc exister naturellement en absence de toute pression médicamenteuse et sont susceptibles d’avoir un impact sur la réponse aux différents traitements par AAD. Notre objectif était de déterminer la prévalence des variants associés à la résistance dans les souches tunisiennes circulantes en préambule à l’introduction deces molécules en Tunisie. Méthodes : L’amplification et le séquençage direct de la protéase NS3, de la polymérase NS5B ainsi que la région NS5A ont été effectuées chez 149 patients tunisiens naïfs de traitement et infectés par le VHC de génotype 1 (génotype 1b = 142 ; génotype 1a = 7). Résultats : Douze séquences NS3 (12/131 ; 9,2%) ont montré des mutations connes pour conférer une résistance aux IP. Une seule séquence (1/95 ; 1,1%) a montré la mutation V321I connue pour conférer une résistance aux IN-NS5B. Trente quatre séquences (34/95 ; 35,8%) ont montré des mutations connues pour diminuer la sensibilité des INN-NS5B. Une seule séquence de génotype 1a (1/7 ; 14,3%) et 17 séquences de génotype 1b (17/112 ; 16,2%) ont montré des mutations connues pour conférer une résistance au inhibiteurs de la protéine NS5A. Conclusions : Notre étude a permis de mettre en évidence la présence de substitutions conférant une diminution de la sensibilité aux AAD chez des patients tunisiens naïfs de tout traitement anti-VHC. Des études in situ seront nécessaires pour évaluer l’impact de ces mutations sur la réponse au traitement
Introduction: Hepatitis C virus (HCV) is a major cause of liver disease worldwide. This RNA virus is responsible for hepatitis C, which leads to the development of cirrhosis and liver cancer. According to the World Health Organization, HCV infects more than 170 million people worldwide, about 3% of the population. Chronic hepatitis C still know in Tunisia low cure rates for genotype 1, because the currently standard treatment available is combination therapy of pegylated interferon plus ribavirin. At present, the development of different molecules that specifically target HCV, called direct-acting antivirals (DAA) appears as a potential revolution in the treatment of HCV infection. These DAA include protease inhibitors (PI), nucleos(t)ide (NI) and non-nucleoside inhibitors (NNI) for NS5B polymerase and NS5A inhibitors. The viral quasispecies is formed by a complex mixture of viral variants including variants associated with variable degrees of resistance to DAA. These variants may therefore exist naturally in absence of drug pressure and may affect response to different treatments by DAA. Our objective was to determine the prevalence of variants associated with resistance in circulating Tunisian strains preamble to the introduction of these molecules in Tunisia. Methods: Amplification and direct sequencing of NS3 protease, NS5B polymerase and NS5A region were performed in 149 Tunisian naïve patients infected with HCV genotype 1 (genotype 1b = 142; genotype 1a = 7) . Results: Twelve sequences NS3 (12/131; 9.2%) showed mutations known to confer resistance to PI. One sequence (1/95; 1.1%) showed the V321I mutation known to confer resistance to NS5B-IN. Thirty four sequences (34/95; 35.8%) showed mutations known to reduce the sensitivity of NS5B-INN. One genotype 1a sequence (1/7; 14.3%) and 17 genotype 1b sequences (17/112; 16.2%) showed mutations known to confer resistance to NS5A inhibitors.Conclusions: Our study highlighted the presence of substitutions conferring decreased susceptibility to DAA in naïve patients infected with HCV genotype 1. Field studies will be needed to evaluate the impact of these mutations on the treatment response
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Meguellati, Amel. "Synthèse de biomolécules agissant comme inhibiteurs de l'ARN polymérase ARN dépendante du virus de l'hépatite C et développement de nouveaux surfactants comme stabilisants des protéines membranaires par réseaux de ponts salins." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GRENV001.

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Le projet de thèse se focalise sur la synthèse de biomolécules et se subdivise en deux parties. La première partie concerne la conception et la synthèse de dérivés de produits naturels d'intérêt thérapeutique nommés aurones en vue de mettre au point de nouvelles molécules à activité antivirale. Récemment, les aurones ont été identifiées comme étant des inhibiteurs de l'ARN-polymérase ARN-dépendante (NS5B) du virus de l'hépatite C (VHC). Cette enzyme, présente chez le virus mais absente chez l'homme, joue un rôle central dans la réplication virale. Suite à ces résultats antérieurs, les efforts ont été poursuivis et, dans le cadre de cette thèse, nous avons entrepris,d'une part, la synthèse d'analogues originaux dont le cycle B des aurones a été remplacé par des hétérocycles et, d'autre part, la synthèse depseudodimères d'aurones dans le but d'affiner les exigences structurales pour améliorer l'effet inhibiteur.L'activité a été évaluée selon des tests enzymatiques et cellulaires et a permis d'identifier quelques candidats doués d'une bonne activité inhibitrice et d'une faible toxicité. La deuxième partie du projet de thèse, sans lien avec la première partie,concerne des aspects plus fondamentaux et porte sur la synthèse de nouveaux surfactants agissant comme agents stabilisants lors des procédures d'extraction et de cristallisation des protéines membranaires. Les surfactants sont des composants clés dans le domaine de la biologie structurale et de la biochimie des protéines membranaire. Ils sont nécessaires pour maintenir les protéines membranaires dans leur état fonctionnel après extraction. La grande majorité des protéines membranaires est riche en résidus basiques à l'interface. Sur la base de cette caractéristique, une nouvelle famille de surfactants est développée et testée sur des protéines membranaires appartenant aux pompes d'efflux ABC multi-résistantes
The PhD project focuses on biomolecules and is divided into two parts. The first part concerns the design and synthesis of natural product derivatives with therapeutic interest in order to develop new molecules with antiviral activity. Recently, aurones were identified as new inhibitors of hepatitis C virus (HCV) NS5B polymerase. Following these results, efforts were continuedand we undertook, on the one hand,the synthesis of original analogues in which the aurone B-ring was replaced by a heterocyclic rings and, on the other hand, the synthesis of aurone pseudodimers in order to refine the structural requirements to improve the inhibitory effect. The potent NS5B inhibitory activity combined with their low toxicity make aurones attractive drug candidates against HCV infection. The second part of the PhD thesis is unrelated to the first part and concerns more fundamental aspects. It focused on the synthesis of new surfactants acting as stabilizing agents during extraction of membrane proteins (PM). Surfactants are required for maintaining PM in their functional state after extraction from membrane lipid matrix. The vast majority of PM shares a net enrichment in basic residues at the interface between membrane and cytoplasm, a property known as the positive inside rule. Based on this feature, a new family of surfactants is developed and tested on membrane proteins belonging to the multidrug ABC efflux pumps family
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Valdau, Olga Verfasser], Dieter [Akademischer Betreuer] [Willbold, and J. [Akademischer Betreuer] Bode. "Untersuchungen zur Rekonstruktion von c-Src-NS5A-NS5B sowie EDD E3-β-Catenin – zweier krankheitsrelevanter Proteinkomplexe / Olga Valdau. Gutachter: Dieter Willbold ; J. Bode." Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2015. http://d-nb.info/1077866798/34.

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Valdau, Olga [Verfasser], Dieter [Akademischer Betreuer] Willbold, and J. [Akademischer Betreuer] Bode. "Untersuchungen zur Rekonstruktion von c-Src-NS5A-NS5B sowie EDD E3-β-Catenin – zweier krankheitsrelevanter Proteinkomplexe / Olga Valdau. Gutachter: Dieter Willbold ; J. Bode." Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2015. http://d-nb.info/1077866798/34.

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Mamigonian, Bessa Luíza. "Investigation of the hepatitis C virus RNA polymerase NS5B in solution by nuclear magnetic resonance and its interaction with intrinsically disordered domain 2 of the NS5A protein." Thesis, Lille 1, 2017. http://www.theses.fr/2017LIL10117/document.

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NS5B est l’ARN polymérase du virus de l’hépatite C (VHC). Sa structure a beaucoup été étudiée par radiocristallographie, elle contient trois sous-domaines appelés doigts, paume et pouce. Cependant, les études structurales de cette protéine en solution sont très limitées. La résonance magnétique nucléaire (RMN) a été utilisée pour étudier NS5B en solution ainsi que son interaction avec différents partenaires. L’emploi d’un échantillon de NS5B (65kDa) perdeuterée et sélectivement enrichie au niveau des méthyles 1 des résidus d’isoleucines a permis d’obtenir un spectre simplifié et de bonne qualité. Cette étude a confirmé la présence d’une dynamique particulière dans le pouce et a permis de mettre en évidence des effets à longues distances que se transmettent aux autres sous-domaines. Cette approche a alors été utilisée pour étudier l’interaction entre NS5B et le domaine 2 de la protéine NS5A (NS5A-D2) du VHC. Celui-ci est un domaine intrinsèquement désordonné qui interagit directement avec NS5B in vitro. Nous avons identifié que NS5A-D2 se lie via deux sites d’interaction sur le sous-domaine du pouce. Puisqu’un de ces sites est le site de liaison de l’inhibiteur allostérique filibuvir, nous avons étudié la liaison de cette molécule à la polymérase. Sa liaison cause des effets à longues distances tout au long de NS5B. Enfin, nous avons caractérisé la liaison d’un ARN simple brin à NS5B et nous avons identifié que NS5A-D2 et filibuvir réduisent mais ne suppriment pas l’interaction de NS5B avec l’ARN. L’analyse de NS5B par RMN en solution a permis d’étudier des interactions et d’accéder à des paramètres dynamiques très complémentaires des études cristallographiques
NS5B is the hepatitis C virus (HCV) RNA-dependent RNA polymerase. This protein has been extensively studied by X-ray crystallography and shows an organization in three subdomains called fingers, palm and thumb. Whereas static crystallographic data are abundant, structural studies of this protein in solution are limited. Nuclear magnetic resonance (NMR) spectroscopy was used to study the 65 kDa NS5B in solution as well as its interaction with binding partners. It was characterized using selective isotopic labeling of isoleucine side-chain methyl groups, which gives rise to a simplified NMR spectrum with an improved signal-to-noise ratio. This characterization confirmed the presence of particular dynamics in the subdomains, especially in the thumb, as well as long-range effects that are transmitted through to other subdomains. Furthermore, this system was used to investigate the binding of the domain 2 of NS5A (NS5A-D2), a disordered domain of another HCV protein that has been shown to directly interact with NS5B in vitro. With paramagnetic relaxation enhancement experiments we showed that NS5A-D2 binds to NS5B via, at least, two binding sites on the thumb subdomain. As one of these sites was the binding site of allosteric inhibitor filibuvir, we characterized the binding of this small molecule to NS5B by NMR and found long-range effects of its binding throughout the polymerase. Finally, we studied the binding of a small RNA template strand to NS5B and found that both NS5A-D2 and filibuvir reduce but do not abolish the interaction between the polymerase and RNA. In sum, NMR spectroscopy was used to study dynamic properties of NS5B and its interactions with binding partners
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Powdrill, Megan. "Characterization of the hepatitis C virus NS5b RNA-dependent RNA polymerase: novel inhibitors and antiviral resistance." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=107791.

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The hepatitis C virus polymerase NS5b is required for replication of the viral genome, making it an attractive target for antiviral development. The polymerase contains no proof-reading activity and generates viral variants during replication with a high degree of genetic heterogeneity, complicating the development of effective antiviral therapies since resistance mutations are readily selected under drug pressure. A successful treatment regimen will likely require a combination therapy that can suppress the emergence of resistance. Here, we have described the mechanism of action of a novel class of polymerase active site inhibitors, pyrophosphate analogues. We studied interactions between these compounds and NS5b in the presence of the resistance mutations G152E and P156L and have identified interactions leading to resistance. Additionally, we have combined the pyrophosphate analogues with a second class of polymerase active site inhibitors, nucleoside analogue inhibitors (NIs). We found that the combination can interfere with excision, a potential mechanism of resistance to NIs. We have also examined fidelity of the polymerase to better understand its contribution to variability in the viral genome. Our biochemical findings suggest that the efficiency of nucleotide mismatch formation during replication influences the prevalence of resistance mutations within the viral quasispecies population. This is supported by deep-sequencing data from an HCV-infected patient cohort. Based on these findings, we have developed a mathematical model showing that combining inhibitors selecting for resistance mutations generated through difficult-to-form nucleotide mismatches could delay the onset of resistance.We extended this study by performing transient kinetic assays to characterize incorporation of NIs by NS5b and compared this to the efficiency of mismatched nucleotide incorporation. These studies demonstrate that current NIs incorporate more efficiently than mismatched nucleotides. The incorporation efficiency of the guanosine analogue ribavirin was low as compared to other NIs tested and also as compared to G:U and U:G mismatches examined in our fidelity study, suggesting its incorporation during RNA synthesis does not cause error catastrophe. Overall, these studies provide a greater understanding of the mechanism of action of polymerase inhibitors, and of the role of the polymerase in the development of antiviral resistance.
La polymérase NS5b du virus de l'hépatite C est nécessaire pour la réplication du génome viral et représente donc une cible importante pour la découverte et le développement de nouveaux médicaments. La polymérase contient aucune activité de relecture et génère des variantes du virus avec un haut degré d'hétérogénéité génétique lors de sa réplication. Ceci nuit au développement de traitements antiviraux efficaces puisque les mutations de résistance sont facilement sélectionnées sous pression de médicaments. Un traitement efficace exigera probablement une combinaison thérapeutique qui pourrait empêcher la résistance. Ici, nous avons décrit le mécanisme d'action d'une nouvelle classe d'inhibiteurs du site actif de la polymérase, les analogues du pyrophosphate. Nous avons étudié les interactions entre ces inhibiteurs et NS5b, en présence des mutations de résistance G152E et P156L en plus d'identifier des interactions conduisant à la résistance. De plus, nous avons combiné les analogues du pyrophosphate avec une deuxième classe d'inhibiteurs du site actif de la polymérase, les inhibiteurs nucléotidiques (INs). Nous avons constaté que la combinaison peut interférer avec l'excision, un mécanisme potentiel de résistance aux INs. Nous avons également examiné la fidélité de la polymérase pour mieux comprendre sa contribution à la variabilité du génome viral. Nos résultats biochimiques suggèrent que l'efficacité de la formation de décalage lors de la réplication influence la prévalence des mutations de résistance au sein de la population virale quasi-espèces. Ceci est soutenu par les données obtenues suite au séquençage à très haut débit d'une cohorte de patients infectés par le VHC. Basé sur ces résultats, nous avons développé un modèle mathématique démontrant que la combinaison d'inhibiteurs qui sélectionnent des mutations de résistance générées par des mésappariements nucléotidiques difficiles à former pourrait retarder l'apparition de la résistance. Nous avons poursuivi cette étude en caractérisant l'incorporation des INs par NS5b et en comparant cela à l'efficacité de l'incorporation de nucléotides dépareillés. Ces études démontrent que les INs actuelles sont incorporées avec plus d'efficacité que les nucléotides dépareillés. L'efficacité d'incorporation de l'analogue ribavirine était faible par rapport aux autres INs testés et aussi par rapport aux mésappariements G: U et U: G examinés dans notre étude de fidélité. Ceci suggère que l'incorporation de la ribavirine lors de la synthèse d'ARN ne provoque pas d'erreur catastrophique. Globalement, ces études nous mènent à une meilleure compréhension du mécanisme d'action des inhibiteurs de la polymérase NS5b, et du rôle de la polymérase dans le développement de la résistance aux antiviraux.
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Dahl, Göran. "Kinetic studies of NS3 and NS5B from Hepatitis C virus : Implications and applications for drug discovery." Doctoral thesis, Uppsala universitet, Institutionen för biokemi och organisk kemi, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-98868.

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The aim of these studies was to increase our understanding of the non-structural proteins 3 and 5B (NS3 and NS5B) from the hepatitis C virus (HCV), and thereby contribute to the development of new and better drugs against HCV. By studying NS3 with substitutions identified to be associated with resistance to NS3 inhibitors in clinical trials (R155Q, A156T and D168V) it was found that not all inhibitors were affected, indicating that cross-resistance can be avoided. Substitutions at position 526 and 528 in the helicase domain of this bifunctional enzyme were introduced and the effect on the protease was investigated. These substitutions affected protease inhibition, showing that the helicase can influence the protease. This interplay between the two domains is also involved in the discovered activation of the enzyme at low inhibitor concentrations. Being a case of "enzyme memory", the phenomenon stresses the importance of using full-length NS3 for enzymatic assays. Inhibitors with novel designs, with presumed increased stability in vivo, were developed and, even though they were found to be of low potency, provide alternative ideas of how to design an inhibitor. Detailed information about the interaction between NS3 and its protein cofactor NS4A or several protease inhibitors were determined using a direct binding assay. The rate constants of the inhibitor interactions were affected by NS4A and it was also possible to visualize time-dependent binding inhibitors. A good correlation between interaction data (Kd or koff) and inhibition data (Ki) or replicon data (EC50) was also seen. The same approach was used for studying the interactions between NS5B and several non-nucleoside inhibitors, providing information of the chemodynamics and giving insights into inhibitor design.   Taken together, all these studies have resulted in new information about, and new tools with which to study, NS3 and NS5B. This is of great importance in the struggle to find new and potent drugs, leading to a cure for HCV infection.
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Choi, Yook-Wah. "Structural and functional characterization of human DDX5 and its interaction with NS5B of hepatitis C virus." University of the Western Cape, 2011. http://hdl.handle.net/11394/5299.

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Philosophiae Doctor - PhD
Hepatitis C was first recognized as a transfusion-associated liver disease not caused by hepatitis A or hepatitis B virus after serological tests were developed to screen for their presence in the blood. The infectious agent was finally identified with the cloning of the cDNA of hepatitis C virus (HCV) using random polymerase chain reaction (PCR) screening of nucleic acids extracted from plasma of a large pool of chimpanzee infected with non-A non-B hepatitis. NS5B, a membrane-associated RNA-dependent RNA polymerase essential in the replication of HCV, initiates the synthesis of a complementary negative-strand RNA from the genomic positive-strand RNA so that more positive-strand HCV RNA can then be generated from the newly synthesised negative-strand template. The crystal structure of NS5B presented typical fingers, palm and thumb sub-domains encircling the GDD active site, which is also seen in other RNA-dependent RNA polymerases, and is similar to the structure of reverse transcriptase of HIV-1 and murine Moloney leukaemia virus. The last 21 amino acids in the C-terminus of NS5B anchor the protein to the endoplasmic reticulum (ER)-derived membranous web. NS5B has been shown to interact with the core, NS3/NS4A, NS4B and NS5A proteins, either directly or indirectly. Numerous interactions with cellular proteins have also been reported. These proteins are mainly associated with genome replication, vesicular transport, protein kinase C-related kinase 2, P68 (DDX5), α-actinin, nucleolin, human eukaryotic initiation factor 4AII, and human VAMP-associated protein. Previous studies have confirmed that NS5B binds to full-length DDX5. By constructing deletion mutants of DDX5, we proceeded to characterize this interaction between DDX5 and HCV NS5B. We report here the identification of two exclusive HCV NS5B binding sites in DDX5, one in the N-terminal region of amino acids 1 to 384 and the other in the C-terminal region of amino acids 387 to 614. Proteins spanning different regions of DDX5 were expressed and purified for crystallization trials. The N-terminal region of DDX5 from amino acids 1 to 305 which contains the conserved domain I of the DEAD-box helicase was also cloned and expressed in Escherichia coli. The cloning, expression, purification and crystallization conditions are presented in this work. Subsequently, the crystal structure of DDX5 1-305 was solved and the high resolution three-dimensional structure shows that in front of domain I is the highly variable and disordered N terminal region (NTR) of which amino acids 51-78 is observable, but whose function is unknown. This region forms an extensive loop and supplements the core with an additional α-helix. Co-immunoprecipitation experiments demonstrated that the NTR of DDX5 1-305 auto-inhibit its interaction with NS5B. Interestingly, the α-helix in NTR is essential for this auto-inhibition and seems to mediate the interaction between the highly flexible 1-60 residues in NTR and NS5B binding site in DDX5 1-305, presumably located within residues 79-305. Furthermore, co-immunoprecipitation experiments revealed that DDX5 can also interact with other HCV proteins, besides NS5B.
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Books on the topic "NS5b"

1

Groeneveld, Gerard. Zo zong de NSB: Liedcultuur van de NSB, 1931-1945. Nijmegen: Uitgeverij Vantilt, 2007.

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Groeneveld, Gerard. Zo zong de NSB: Liedcultuur van de NSB, 1931-1945. Nijmegen: Uitgeverij Vantilt, 2007.

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Lindholt, Tore. Avsporing: Kampen om NSB. Oslo: Gyldendal norsk forlag, 1990.

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Vermeer, Annemarie. NSB-films : propaganda of vermaak? Beetsterzwaag: AMA boeken, 1987.

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Mussert & Co: De NSB-leider en zijn vertrouwelingen. Amsterdam: Boom, 2012.

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De tweede generatie: Herinneringen van een NSB-kind. Utrecht: Spectrum, 1985.

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Mussert, Anton Adriaan. Nagelaten bekentenissen: Verantwoording en celbrieven van de NSB-leider. Nijmegen: Vantilt, 2005.

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Dubbele tongen en giftige pennen: Het verhaal van een NSB-kind. Houten: Van Reemst, 1997.

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Bukman, Bert. Anton: Mussert en de NSB : opkomst en ondergang van een populist. Amsterdam: Meulenhoff, 2013.

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Universities, National Science Board (U S. ). Committee on Foreign Involvement in U. S. Report of the NSB Committee on Foreign Involvement in U.S. Universities. Washington, DC: National Science Foundation, 1989.

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Book chapters on the topic "NS5b"

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Watkins, William J. "Evolution of HCV NS5B Non-nucleoside Inhibitors." In Topics in Medicinal Chemistry, 171–91. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/7355_2018_35.

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Cho, Aesop. "Evolution of HCV NS5B Nucleoside and Nucleotide Inhibitors." In Topics in Medicinal Chemistry, 117–39. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/7355_2018_36.

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Hagedorn, C. H., E. H. van Beers, and C. De Staercke. "Hepatitis C Virus RNA-Dependent RNA Polymerase (NS5B Polymerase)." In Current Topics in Microbiology and Immunology, 225–60. Berlin, Heidelberg: Springer Berlin Heidelberg, 2000. http://dx.doi.org/10.1007/978-3-642-59605-6_11.

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Schinazi, Raymond F., Junxing Shi, and Tony Whitaker. "Sofosbuvir (Sovaldi): The First-in-Class HCV NS5B Nucleotide Polymerase Inhibitor." In Innovative Drug Synthesis, 61–80. Hoboken, NJ, USA: John Wiley & Sons, Inc, 2015. http://dx.doi.org/10.1002/9781118819951.ch4.

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Donald, Alastair. "Sovaldi, an NS5B RNA Polymerase-Inhibiting Carboxylic Acid Ester Used for the Treatment of Hepatitis C Infection." In Bioactive Carboxylic Compound Classes: Pharmaceuticals and Agrochemicals, 167–76. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2016. http://dx.doi.org/10.1002/9783527693931.ch12.

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Cleiren, Erna, Benoit Devogelaere, and Katleen Fierens. "Surface Plasmon Resonance as a Tool to Select Potent Drug Candidates for Hepatitis C Virus NS5B Polymerase." In Antiviral Methods and Protocols, 129–36. Totowa, NJ: Humana Press, 2013. http://dx.doi.org/10.1007/978-1-62703-484-5_11.

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Beaulieu, Pierre L. "CHAPTER 8. Design and Development of NS5B Polymerase Non‐nucleoside Inhibitors for the Treatment of Hepatitis C Virus Infection." In Drug Discovery, 248–94. Cambridge: Royal Society of Chemistry, 2013. http://dx.doi.org/10.1039/9781849737814-00248.

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LaFemina, Robert L. "Hepatitis C Virus Genetics and the Discovery of Mechanism-Based Inhibitors of the NS3/4A Protease and NS5B Polymerase." In Translational Research in Biomedicine, 63–93. Basel: KARGER, 2008. http://dx.doi.org/10.1159/000140936.

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Ferrari, Eric, and Hsueh-Cheng Huang. "A Novel Hepatitis C Virus NS5B Polymerase Assay of De Novo Initiated RNA Synthesis Directed from a Heteropolymeric RNA Template." In Antiviral Methods and Protocols, 81–92. Totowa, NJ: Humana Press, 2013. http://dx.doi.org/10.1007/978-1-62703-484-5_7.

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Koletzki, Diana, Theresa Pattery, Bart Fevery, Leen Vanhooren, and Lieven J. Stuyver. "Amplification and Sequencing of the Hepatitis C Virus NS3/4A Protease and the NS5B Polymerase Regions for Genotypic Resistance Detection of Clinical Isolates of Subtypes 1a and 1b." In Antiviral Methods and Protocols, 137–49. Totowa, NJ: Humana Press, 2013. http://dx.doi.org/10.1007/978-1-62703-484-5_12.

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Conference papers on the topic "NS5b"

1

Dietz, J., J. Vermehren, KH Peiffer, B. Müllhaupt, P. Buggisch, K. Matschenz, J. Schattenberg, et al. "Persistenz von HCV Resistenz-assoziierten Substitutionen in NS3, NS5A und NS5B nach einem DAA Therapieversagen." In Viszeralmedizin 2019. Georg Thieme Verlag KG, 2019. http://dx.doi.org/10.1055/s-0039-1695334.

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2

Rupp, C., T. Hippchen, P. Sauer, J. Pfeiffenberger, W. Stremmel, P. Schemmer, DN Gotthardt, A. Mehrabi, and KH Weiss. "High SVR12 rates with combination of NS5A- and NS5B- inhibitors for 24 weeks in liver transplanted patients." In Viszeralmedizin 2017. Georg Thieme Verlag KG, 2017. http://dx.doi.org/10.1055/s-0037-1605033.

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Moraes, Paula de F. de, Raquel A. C. Leão, Daniel Brian Nichols, Amartya Basu, Maksim Chudayeu, Tanaji T. Talele, Neerja Kaushik-Basu, and Paulo R. R. Costa. "Coumarins and Neoflavones: Synthesis and HCV NS5B Polymerase Inhibition." In 15th Brazilian Meeting on Organic Synthesis. São Paulo: Editora Edgard Blücher, 2013. http://dx.doi.org/10.5151/chempro-15bmos-bmos2013_2013818222912.

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4

"ASME Conference Presenter Attendance Policy and Archival Proceedings." In ASME 2014 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASME, 2014. http://dx.doi.org/10.1115/detc2014-ns5b.

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5

"ASME Conference Presenter Attendance Policy and Archival Proceedings." In ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition. ASME, 2017. http://dx.doi.org/10.1115/gt2017-ns5b.

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6

"ASME Conference Presenter Attendance Policy and Archival Proceedings." In ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition. ASME, 2018. http://dx.doi.org/10.1115/gt2018-ns5b.

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7

"ASME Conference Presenter Attendance Policy and Archival Proceedings." In ASME 2015 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASME, 2015. http://dx.doi.org/10.1115/detc2015-ns5b.

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"ASME Conference Presenter Attendance Policy and Archival Proceedings." In ASME 2015 34th International Conference on Ocean, Offshore and Arctic Engineering. ASME, 2015. http://dx.doi.org/10.1115/omae2015-ns5b.

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"ASME Conference Presenter Attendance Policy and Archival Proceedings." In ASME 2017 36th International Conference on Ocean, Offshore and Arctic Engineering. ASME, 2017. http://dx.doi.org/10.1115/omae2017-ns5b.

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"ASME Conference Presenter Attendance Policy and Archival Proceedings." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. ASME, 2013. http://dx.doi.org/10.1115/gt2013-ns5b.

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Reports on the topic "NS5b"

1

Lentini, J., and R. Tewari. Namespace Database (NSDB) Protocol for Federated File Systems. Edited by C. Lever. RFC Editor, March 2015. http://dx.doi.org/10.17487/rfc7532.

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May Robin Chaffin. NSTB Assessments Summary Report: Common Industrial Control System Cyber Security Weaknesses. Office of Scientific and Technical Information (OSTI), May 2010. http://dx.doi.org/10.2172/983345.

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